Micromachined electrolyte sheet

ABSTRACT

The disclosure relates to ceramic lithium ion electrolyte membranes and processes for forming them. The ceramic lithium electrolyte membrane may comprise at least one ablative edge. Exemplary processes for forming the ceramic lithium ion electrolyte membranes comprise fabricating a lithium ion electrolyte sheet and cutting at least one edge of the fabricated electrolyte sheet with an ablative laser.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of patent application Serial No.13/249,935 filed on Sep. 30, 2011, and claims the benefit of priority toU.S. patent application Ser. No. 13/249,935 filed on Sep. 30, 2011, thecontent of which is relied upon and incorporated herein by reference inits entirety.

FIELD OF THE DISCLOSURE

The disclosure relates to lithium ion electrolyte membranes andprocesses for forming the same. In various embodiments, the lithium ionelectrolyte membrane may comprise at least one ablative edge. In furtherembodiments, the processes for forming a lithium ion electrolytemembrane comprises fabricating a lithium ion electrolyte sheet andcutting at least one edge of the fabricated electrolyte sheet with anablative laser to form an ablative edge.

BACKGROUND

Electrolyte membranes are known in the art, such as, for example, foruse in battery structures and fuel cells. For example, U.S. PatentApplication Publication No. 2009/0081512 describes zirconia-basedceramic electrolyte membranes and related methods of making by lasermicromachining techniques. Other electrolyte membrane materials arebased on lithium metal phosphates (“LMP”) such as Lithium TitaniumPhosphate (“LTP”), and may comprise LTP wherein a fraction of thetitanium is replaced by Aluminum (“LATP”). It is well known that LMPelectrolyte membranes are distinct from, and have different propertiesthan, zirconia-based electrolyte membranes.

Thin LMP membranes may be desired in certain applications, for exampleto improve the membrane conductance, which is directly proportional tothe membrane thickness. Conventional LMP-based membranes typically haveconductivity of about 5×10⁻⁴ S/cm, and a conductance of approximately0.02 S. Membranes with conductance of about 0.05 S, or more preferablyabout 0.1 S or higher, are desirable in certain applications.Furthermore, it is known that these targets can be achieved by reducingthe membrane thickness, for example to about 100 μm (0.05 S) or about 50μm (0.1 S).

However, although thinner LMP membranes may be more desirable, forexample in battery structure applications where a thinner membraneprovides lower impedance and thus, lower internal resistance and higherpower capability, it is generally difficult to make thin membraneshaving sufficiently precise dimensions with known methods, for exampledue to limits of mechanical cutting technology. Additionally, thin LMPmembranes are typically fragile, and therefore difficult to fabricateand handle. For example, conventional mechanical cutting processes limitLMP membrane thickness to about 200 μm. This is particularly true whenthe membrane is unsupported, i.e., where the membrane is not integratedinto a multi-layer structure wherein some other layer providesmechanical support.

In addition to the foregoing, polycrystalline electrolyte membranestypically have large grain boundary resistance compared to intra-grainresistance. Therefore, typical ceramic electrolyte membranes are oftenlarge-grained in order to minimize grain boundary effects. However, thinelectrolyte membranes with large grains are typically weak andfine-grained ceramic membranes are mechanically superior to conventionalceramic membranes. Also, the mechanical properties of thin membranes canbe severely degraded by edge defects and wrinkling that occurs duringprocessing. For example, edge defects may be produced where the cuttingprocess introduces microstructural features that may become points ofstress concentration, thus reducing strength. Defects such as grossaccumulation of melted material or voids resulting from substantialmovement of melted material are undesirable in at least certainembodiments, as they may degrade mechanical properties if they aresignificant enough to influence stress distribution within the membrane.Further, it can be difficult, using conventional mechanical methods, toprepare an LMP electrolyte membrane having precise dimensions, due toshrinking during firing.

There is, therefore, a need to provide mechanically strong, thin,fine-grained ceramic lithium ion electrolyte membranes with highquality, defect-free edges.

SUMMARY

In accordance with the detailed description and various exemplaryembodiments described herein, the disclosure relates to lithium ionelectrolyte membranes and processes for forming the same. In variousembodiments, the lithium ion electrolyte membranes may comprise at leastone ablative edge. In various embodiments, the ablative edge may belithium-enriched relative to the bulk of the membrane. In furtherembodiments, the membrane may be a ceramic lithium ion electrolytemembrane and may, in various examples, be supported or unsupported.

In at least certain embodiments, the lithium ion electrolyte membranesmade according to the disclosure may be one or more of mechanicallystrong, dense, hermetic, flat, wrinkle-free, thin, pore-free, andfine-grained, and may comprise one or more substantially defect-freeedges, particularly in comparison to pre-cut lithium ion electrolytemembranes. In addition, relative to previously known methods, it may bepossible to fabricate lithium ion electrolyte membranes havingsubstantially precise dimensions. However, it should be noted that atleast certain embodiments according to the disclosure may not have oneor more of the above-mentioned properties, yet such embodiments areintended to be within the scope of the disclosure.

BRIEF DESCRIPTION OF DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings are not intended to berestrictive of the invention as claimed, but rather are provided toillustrate exemplary embodiments of the invention and, together with thedescription, serve to explain the principles of the invention.

FIG. 1A is a 1500× SEM micrograph of an ablative edge of a lithium ionelectrolyte membrane, formed according to an embodiment of thedisclosure;

FIG. 1B is a 5000× SEM micrograph of the ablative edge of a lithium ionelectrolyte membrane, as seen in FIG. 1A;

FIG. 2A is an STEM image of an ablative edge of a lithium ionelectrolyte membrane, formed according to an embodiment of thedisclosure;

FIG. 2B is an elemental analysis plot of the lithium content of theablative edge of a lithium ion electrolyte membrane as seen in FIG. 2A;

FIG. 2C shows a further elemental analysis plot of the lithium contentof the ablative edge of a lithium ion electrolyte membrane as seen inFIG. 2A, measured from 0 to 1200 nm into the surface of the edge; and

FIG. 3 shows a graphical depiction of the failure probability of an LATPmembrane made according to an embodiment of the invention, and an LATPmembrane made according to traditional shrink-to-fit methods.

DETAILED DESCRIPTION

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory onlyand are not restrictive of the invention as claimed. Other embodimentswill be apparent to those skilled in the art from consideration of thespecification and practice of the embodiments disclosed herein. It isintended that the specification and examples be considered as exemplaryonly, with the true scope and spirit of the invention being indicated bythe claims.

It is also to be understood that, while in various embodiments describedherein, steps of exemplary processes disclosed are recited in aparticular order, it is intended that the disclosed process steps may becarried out in any order that one of skill in the art would understandwould not significantly change the desired product.

As used herein the articles “the,” “a,” or “an,” mean “at least one,”and should not be limited to “only one” unless explicitly indicated tothe contrary. Thus, for example, the use of “the ablative edge” or “anablative edge” is intended to mean at least one ablative edge.

The disclosure relates, in various embodiments, to methods of formingceramic lithium ion electrolyte membranes, for example LMP electrolytemembranes, having at least one ablative edge. The at least one ablativeedge may, in various embodiments, be substantially defect-free. Themethods described herein may, in at least some embodiments, allow forpreparation of a ceramic lithium ion electrolyte membrane having athickness of about 400 μm or less, such as about 300 μm or less, forexample about 200 μm or less. In further exemplary embodiments, themethods described herein may allow for an unsupported ceramic lithiumion electrolyte membrane to be formed.

In further embodiments, the methods described herein may be used to formlithium ion electrolyte membranes having a fine-grained structure. Largegrains are considered to be defects in certain applications, and maydegrade the mechanical properties of the membrane. In general it isdesired that, in the vicinity of the cut edge, microstructural featuresformed from the cutting process be no more than about one-third timesthe thickness of the membrane. In further embodiments, the size ofmicrostructural features introduced from the cutting process may be lessthan about ⅓ the thickness of the membrane, such as, for example, lessthan 1/10 the thickness of the membrane. For structures formed by thecutting process that exhibit a high aspect ratio, such as fibers orsheets, the diameter or thickness, respectively, may ideally, in atleast some embodiments, be no more than about one-third times thethickness of the membrane.

Various exemplary methods of forming lithium ion electrolyte membranesdescribed herein comprise steps of forming a sintered electrolytemembrane by tape casting methods, followed by laser micromachining themembrane to produce the desired electrolyte membrane.

Exemplary tape casting processes are known. Starting materials chosen toprovide an LMP composition, such as, for example, an LTP or LATPcomposition may be mixed in an appropriate ratio. By way of example,starting materials for making LATP may be chosen from lithium carbonate,aluminum hydroxide, titanium oxide, ammonium dihydrogen phosphate, andphosphoric acid. In various embodiments, the LMP composition may bechosen from LATP compositions of the general formula Li_((1+x))M^(III)_((x))M^(IV) _((2−x))(PO₄)₃, where M^(III) is a 3+ metal ion such asAl³⁺, La³⁺, Ga³⁺, etc., and M^(IV) is a 4+ metal ion such as Ti⁴⁺, Ge⁴⁺,Sn⁴⁺, etc. For other 3+ metals, the aluminum hydroxide may be replacedby lanthanum hydroxide or gallium hydroxide, for example. For other 4+metals, the titanium oxide may be replaced by germanium oxide or tinoxide, for example. In at least one embodiment, for example, the LMPcomposition may be chosen from Li_(1.4)Al_(0.4)Ti_(1.6)(PO₄)₃.

After mixing, the starting materials may be treated in such a way as toform a powder. Such treatments are known to those of skill in the art.For example, the starting materials may be calcined or otherwise reactedto form the desired phase. Alternatively, the starting materials may bereacted in solution, for example in a sol-gel synthesis.

By way of example only, in at least one embodiment, the startingmaterials may be calcined at temperatures ranging from about 400° C. toabout 1000° C., such as about 600° C. to about 800° C. It may bedesirable to calcine the starting materials in a vessel that does notreact with or otherwise degrade the mixed starting materials during theprocess, such as, for example, a platinum crucible.

The mixed phase product may then be further processed in any way knownto those of skill in the art (e.g. broken up, crushed to a coarsepowder, and/or milled) so as to provide a powder that has a particlesize of less than about 5 μm, such as less than about 2 μm, or less thanabout 1 μm. An LMP composition may, in at least one exemplaryembodiment, have a particle size of less than about 0.5 μm, such asabout 0.3 μm.

Once the desired particle size is achieved, a slip for a tape castingprocess may be prepared by combining the powder with components such as,for example, solvents (for example organic solvents and/or water),strengthening plasticizers, dispersants, binders, and/or any othercomponent known in the art to be useful in preparing a slip for tapecasting.

In at least one exemplary embodiment, phosphate additives may optionallybe added to the composition, for example up to about 10 wt. %, such asup to about 7 wt. %, or up to about 5 wt. % of the inorganic solidscontent. In one exemplary embodiment, phosphate additives may optionallybe added at an amount ranging from about 0.5 to about 5 wt. % of theinorganic solids content. In at least one embodiment, phosphoric acid ischosen. While not wishing to be bound by theory, it is believed thatphosphate additives may promotes densification, while maintaining a finegrained structure.

The cast tape may then be dried by any method known, after which thetape can be released and cut. It may be desirable, in at least certainembodiments, to cut the tape oversized relative to the desired finisheddimensions, to allow for shrinking during heat treatment, and furthertrimming after heating.

Once cut, the tape may be heat treated to form an electrolyte sheet. Forexample, the tape may be fired at a temperature in the range of about700° C. to about 1200° C., such as about 800° C. to about 900° C. In oneexemplary embodiment, the tape is sintered at a temperature of about900° C. The temperature and duration of the heat treatment can be chosenby those of skill in the art such that, once complete, electrolytesheets are produced having a relative density of greater than about 90%,such as greater than about 95% or greater than about 97%, and/or anaverage grain size of less than about 10 μm, such as less than about 5μm, less than about 3 μm, or less than about 1 μm. For example, the tapemay be heated for about 1 to about 5 hours, such as about 2 to about 3hours, such as, for example, about 2 hours.

After the electrolyte sheet is formed, it may be micromachined by meansof an ablative laser, in order to produce an electrolyte membrane havingat least one ablative edge. Ablative lasers are known in the art, andany laser useful in the methods described herein may be used. It may bedesirable, in at least certain embodiments, to avoid using lasers withhigh temperatures, which can cause local melting. Formation of moltenmaterial can result in very large grains in the vicinity of the cut,which may be desirable to avoid for at least certain applications.

It has been found that using an ablative laser may give the electrolytemembrane a physical appearance and characteristics similar to that of asintered edge (i.e., melted) along the cut edge, without actuallymelting the material. This is of particular interest for at leastcertain applications, because such an edge is believed to impartimproved physical properties, such as, for example, improved mechanicalstrength, density, and hermeticity, while providing an edge that issubstantially flat, wrinkle-free, thin, pore-free, and fine-grained,relative to the uncut electrolyte sheet. The micromachined edge appearsto have some amorphous characteristics, but there may be some remainingcrystallinity.

The electrolyte sheet can be placed on an appropriate support and cut tothe desired final dimensions with the ablative laser. As a non-limitingexample, an LMP electrolyte membrane may be cut using a Nd:YVO₄ laserhaving a wavelength of less than about 2 μm, a fluence of less thanabout 250 Joules/cm², repetition rate between about 20 Hz and 100 MHz,and cutting speed of at least about 10 mm/sec. Further examples ofablative lasers that may be used include, but are not limited to, apicosecond laser operating at 355 nm laser wavelength, with a repetitionrate of 1 MHz; a femtosecond laser operating at a wavelength of 1560 nm,10 μJ pulse energy, 1 MHz repetition rate, and pulse duration of lessthan 700 fs; and a nanosecond 355 nm laser, operating at 100 kHz.

The ablative laser may, in various embodiments, be used to produce anLMP membrane that is less than about 400 μm thick, such as less thanabout 200 μm thick or less than about 100 μm thick. By way of example,the membrane may be about 25 μm to about 200 μm, such as about 40 μm toabout 100 μm thick. The process may allow formation of a ceramic lithiumion electrolyte sheet having an ablative edge with a depth of less thanabout 5 μm, such as less than about 3 μm, for example less than about 2μm.

It may be desirable, in certain embodiments, to employ one or more thanone form of motion during the cutting process. For example, the laser,the support holding the electrolyte sheet, or both may be staged for theprocess. By way of non-limiting example, depending on the laserrepetition rate chosen, multiple-pass laser cutting may involve movingthe electrolyte sheet relative to the laser beam at a speed which ismuch higher than the effective cutting speed. The relative motion of theelectrolyte material with respect to the laser beam may optionally beachieved with mechanical stages (mechanical scanning, involving motionby the support), by scanning the laser beam with an optical scanningdevice such as a galvanometer (optical scanning, which may uselight-weight mirrors mounted on a motor), or some combination thereof.In at least certain exemplary embodiments, optical scanning may bepreferred at high speed cutting operations because it enables uniformcutting at tight corner radius.

The number of passes made by the laser will vary depending on, forexample, the thickness and material of the sheet and the parameters ofthe laser, and can easily be determined by those of skill in the art.For example, an LATP electrolyte sheet having a thickness of about 100μm may require approximately 100 passes to ablate completely through thesheet.

Further embodiments according to the disclosure relate to ceramiclithium-ion electrolyte membrane comprising at least one ablative edgecomprising a depth of less than about 5 μm, which may optionally be anouter edge. In the example of a two-dimensional membrane (membranesheet), the depth of the ablative edge is measured normal to thethickness of the membrane. The at least one ablative edge, and the areaof the membrane directly adjacent the ablative edge, may be enrichedwith lithium relative to the non-ablated (bulk) of the membrane. Invarious embodiments, the membrane may be comprised of grains having anaverage grain size of less than about 5 μm, have a relative density ofgreater than 90%, and comprise a thickness of up to about 200 μm.

As can be seen in the SEM (scanning electron microscopy) micrograph ofFIG. 1A, an exemplary LATP electrolyte membrane 100 having an ablativeedge 110 demonstrates the appearance of a smooth, glassy surface. FIG.1B is a greater magnification of the ablative edge 110 of FIG. 1A, andmore clearly shows the desired properties in the ablative edge, such as,for example, the ablative edge has few open pores and is substantiallyfine-grained, flat, wrinkle-free, and hermetic. During laser cutting,some liquid phase sintering appears to take place, thereby forming athin, smooth shell, as also seen in FIG. 1B. In FIG. 1A, line 120denotes the thickness of the ablative edge, as described herein.

FIG. 2A shows an STEM (scanning transmission electron microscopy)micrograph of an exemplary LATP electrolyte membrane 200. Line 240 showsa line of measurement of the elemental analysis perpendicular to andthrough the ablative edge 210, penetrating into the depth of themembrane 200, over a range of slightly more than 5.0 μm. The firstapproximately 0.1 μm of line 240 is shown penetrating a platinum layer230 adjacent the ablative edge 210 (added to protect the surface duringfocused ion beam sample preparation). FIGS. 2B and 2C show the elementalanalysis along line 240. As can be seen from FIGS. 2B and 2C, the region250 of the membrane 200 at or near the ablative edge 210 shows anincreased amount of lithium, relative to the remainder (bulk) 260 of themembrane 200 that is further from the ablative edge 210. FIG. 2Cdemonstrates that the region 250 of the membrane 200 at or near theablative edge 210 is enriched with approximately 18% more lithiumrelative to the amount of lithium present in the remainder 260 of themembrane 200. Without wishing to be bound by theory, it is believed thatthe enrichment of lithium at or near the ablative edge influences themicrostructure of the formed edge. For example, lithium may be expectedto promote the liquid phase formation.

FIG. 3 demonstrates via a 3-point bend test that a membrane according toan exemplary embodiment of the disclosure exhibits greater strength thanone made according to a traditional, shrink-to-fit method. In FIG. 3,the filled diamonds correspond to a comparative shrink-to-fit sample,and the open rectangles correspond to an inventive membrane.

As used herein, the phrase “substantially mechanically strong,” andvariations thereof, means that the electrolyte membrane has a 2-pointstrength greater than that of the uncut electrolyte sheet, such as, forexample, greater than about 50 MPa.

As used herein, the phrase “substantially dense,” and variationsthereof, means having a relative density of at least about 90%, such asabout 95%.

As used herein, the phrase “substantially hermetic,” and variationsthereof, means that within the sealed region of the electrolytemembrane, there is substantially no interconnected porosity, such that aliquid would not be able to migrate in that region.

As used herein, the phrase “substantially flat,” and variations thereof,means there are no height variations greater than 1 mm from a baselinein a perimeter trace of the membrane along a circumferential edge.

As used herein, the phrase “substantially wrinkle free,” and variationsthereof, means that a trace at the edge of the electrolyte membrane issubstantially flat within about 1 mm of the edge.

As used herein, the phrase “substantially pore free,” and variationsthereof, means that the electrolyte membrane is substantially free ofopen pores.

As used herein, the phrase “substantially thin,” and variations thereof,means that the electrolyte membrane is less than 200 μm thick, such asless than about 100 μm thick.

As used herein, the phrase “substantially fine grained,” and variationsthereof, means that the grain size within the electrolyte membrane isless than about 5 μm, such as less than about 2 μm.

As used herein, the phrase “substantially precise dimensions,” andvariations thereof, means that the electrolyte membrane is formed towithin about 98% or the target dimensions.

As used herein, the phrase “substantially defect-free edge,” andvariations thereof, means, in at least one embodiment, edges havingmicrostructural features introduced from the cutting process that are nogreater than about ⅓ the thickness of the membrane, such as, forexample, no greater than 1/10 the thickness of the membrane.

As used herein, the phrase “ablative edge,” and variations thereof,means an edge that has been formed by ablative laser.

Unless otherwise indicated, all numbers used in the specification andclaims are to be understood as being modified in all instances by theterm “about,” whether or not so stated. It should also be understoodthat the precise numerical values used in the specification and claimsform additional embodiments of the invention, and are intended toinclude any ranges which can be narrowed to any two end points disclosedwithin the exemplary values provided. Efforts have been made to ensurethe accuracy of the numerical values disclosed herein. Any measurednumerical value, however, can inherently contain certain errorsresulting from the standard deviation found in its respective measuringtechnique.

EXAMPLE

The following Example is intended to be non-restrictive and explanatoryonly, with the scope of the invention being defined by the claims.

Fabrication of Tape-Cast LATP Electrolyte Sheet

Starting materials comprising lithium carbonate, aluminum hydroxide,titanium oxide, and ammonium dihydrogen phosphate were mixed in anappropriate ratio to produce Li_(1.4)Al_(0.4)Ti_(1.6)(PO₄)₃. The mixedmaterials were then calcined at 700° C. in a platinum crucible. Themixed phase product was then broken up and jet milled until the particlesize was less than about 10 μm, and then subjected to a secondcalcination at 700° C. The process was found to produce nearly pure LATPwith the NASICON-type structure. The product was again broken up,crushed to a coarse powder, and wet attrition-milled in ethanol, toproduce a product having an average particle size of about 0.3 μm. Toprepare the slip, polyvinyl butyral binder, dibutyl phthalateplasticizer, and PS-236 dispersant were added at levels appropriate forproducing a slip which produces a high quality casting. Next, phosphoricacid in an amount of approximately 2 wt % P₂O₅ of the inorganic solidscontent was added and further mixed.

The tape was then air dried, released, and cut. Finally, the tape wassintered at 900° C. for 2 hours. The resulting electrolyte sheet wasfound to have a relative density over 95%, determined by buoyancy, andan average grain size greater than 10 μm, determined by SEM imageanalysis.

Laser Cutting

The oversized electrolyte sheet was then placed on a support and cut tothe desired finished dimensions with an ablative laser, afrequency-tripled Nd:YVO₄ laser. The laser had a wavelength of 355 nm, arepetition rate of 50 kHz, a cutting speed of 230 mm/sec, and a fluenceof 190 J/cm².

It is noted that recitations herein refer to a component of the presentinvention being “configured” or “adapted to” function in a particularway. In this respect, such a component is “configured” or “adapted to”embody a particular property, or function in a particular manner, wheresuch recitations are structural recitations as opposed to recitations ofintended use. More specifically, the references herein to the manner inwhich a component is “configured” or “adapted to” denotes an existingphysical condition of the component and, as such, is to be taken as adefinite recitation of the structural characteristics of the component.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the present inventionwithout departing from the spirit and scope of the invention. Sincemodifications combinations, sub-combinations and variations of thedisclosed embodiments incorporating the spirit and substance of theinvention may occur to persons skilled in the art, the invention shouldbe construed to include everything within the scope of the appendedclaims and their equivalents.

What is claimed:
 1. A ceramic lithium-ion electrolyte membranecomprising at least one ablative edge, wherein the at least one ablativeedge is an outer edge; grains having an average grain size of less thanabout 5 μm; a relative density greater than about 90%; and a thicknessof up to about 200 μm; and wherein the membrane has a 2-point strengthgreater than about 50MPa.
 2. The ceramic lithium-ion electrolytemembrane of claim 1, wherein the at least one ablative edge is enrichedwith lithium, relative to a bulk of the membrane.
 3. The ceramiclithium-ion electrolyte membrane of claim 1, wherein the ablative edgehas an amorphous surface.
 4. The ceramic lithium-ion electrolytemembrane of claim 1, wherein the thickness is less than about 100 μm. 5.The ceramic lithium-ion electrolyte membrane of claim 4, wherein thethickness is at least about 40 μm.
 6. The ceramic lithium-ionelectrolyte membrane of claim 1, wherein within the electrolyte membranethere is substantially no interconnected porosity such that theelectrolyte membrane is hermetic.
 7. The ceramic lithium-ion electrolytemembrane of claim 1, wherein the membrane is unsupported mechanically,not integrated into a multi-layer structure.
 8. A ceramic lithium-ionelectrolyte membrane comprising at least one ablative edge, wherein theat least one ablative edge is an outer edge; grains having an averagegrain size of less than about 5 μm; a relative density greater thanabout 90%; and a thickness of up to about 200 μm, and wherein the outeredge has no height variations greater than 1 mm from baseline in aperimeter trace.
 9. The ceramic lithium-ion electrolyte membrane ofclaim 8, wherein the at least one ablative edge is enriched withlithium, relative to a bulk of the membrane.
 10. The ceramic lithium-ionelectrolyte membrane of claim 8, wherein the ablative edge has anamorphous surface.
 11. The ceramic lithium-ion electrolyte membrane ofclaim 8, wherein the thickness is less than about 100 μm.
 12. Theceramic lithium-ion electrolyte membrane of claim 11, wherein thethickness is at least about 40 μm.
 13. The ceramic lithium-ionelectrolyte membrane of claim 8, wherein within the electrolyte membranethere is substantially no interconnected porosity such that theelectrolyte membrane is hermetic.
 14. The ceramic lithium-ionelectrolyte membrane of claim 8, wherein the membrane is unsupportedmechanically, not integrated into a multi-layer structure.
 15. A ceramiclithium-ion electrolyte membrane comprising at least one ablative edge,wherein the at least one ablative edge is an outer edge; grains havingan average grain size of less than about 5 μm; a relative densitygreater than about 90%; and a thickness of up to about 200 μm; andwherein microstructural features of the ablative edge introduced fromcutting are no greater than about ⅓ the thickness of the membrane. 16.The ceramic lithium-ion electrolyte membrane of claim 15, wherein the atleast one ablative edge is enriched with lithium, relative to a bulk ofthe membrane.
 17. The ceramic lithium-ion electrolyte membrane of claim15, wherein the ablative edge has an amorphous surface.
 18. The ceramiclithium-ion electrolyte membrane of claim 15, wherein the thickness isless than about 100 μm.
 19. The ceramic lithium-ion electrolyte membraneof claim 18, wherein the thickness is at least about 40 μm.
 20. Theceramic lithium-ion electrolyte membrane of claim 15, wherein within theelectrolyte membrane there is substantially no interconnected porositysuch that the electrolyte membrane is hermetic.
 21. The ceramiclithium-ion electrolyte membrane of claim 15, wherein the membrane isunsupported mechanically, not integrated into a multi-layer structure.